Photographic materials for the silver dyestuff bleaching process



United States Patent 0 "cc 3,455,695 PHOTOGRAPHIC MATERIALS FOR THE SILVER DYESTUFF BLEACHING PROCESS Bernhard Piller, Marly-le-Petit, Switzerland, assignor to Ciba Limited, Basel, Switzerland, a Swiss company No Drawing. Filed Feb. 15, 1966, Ser. No. 527,495 Claims priority, application Switzerland, Feb. 22, 1965, 2,426/ 65 Int. Cl. G03c 1/10 U.S. Cl. 96-99 6 Claims ABSTRACT OF THE DISCLOSURE The present invention provides photographic materials for the silver dye bleaching process comprising a support carrying a layer containing a silver halide emulsion and a dyestuff. The dyestuff corresponds to the formula HOaS Where X represents a hydrogen or halogen atom, or an alkyl, alkoxy, hydroxyalkoxy, alkoxyalkoxy or acylamino group, and Y represents a hydrogen atom, an alkyl or an alkoxy group. These dyestuffs are fast to diffusion and light and are easily reduced in the dye bleaching bath.

The resulting positive images are fast to light and of the 30 permanence required for documents.

The present invention provides photographic materials for the silver dye bleaching process comprising a support 35 carrying a layer containing a dyestuff of the formula where X represents a hydrogen or halogen atom, or an alkyl, alkoxy, hydroxyalkoxy, alkoxyalkoxy or acylamino group, and Y represents a hydrogen atom, an alkyl group 7 or an alkoxy group.

Preferred dyestuffs are those of the formula where -X and Y have the meanings given above.

The dyestuffs of the Formula 1 may be obtained by reacting a dihalide of a pyridine dicarboxylic acid in a 3,455,695 Patented July 15, 1969 molecular ratio of 1:2 with an aminoazo dyestuff of the formula SIO3H where X and Y have the meanings defined above. It is advantageous to carry out this reaction with a pyridine dicarboxylic acid dichloride, for example with the dichloride of pyridine-2,5-dicarboxylic acid, pyridine-3,5-dicarboxylic acid or especially pyridine-2,6-dicarboxylic acid. The aminoazo dyestuffs of the Formula 3 may be obtained by coupling diazotized 2-aminonaphthalene-4,8-disulphon- SOzH Other wise, the dyestuffs of the Formulae 1, 2 and 3 may be manufactured by any known method. The coupling to form the aminoazo dyestuffs is carried out in an acid medium. Amines that are difiicult to couple may be 5 coupled in the form of their w-methanesulfonic acids, followed by elimination of the methanesulfonic acid group.

The aminoazo dyestuffs may be reacted, for example, with the pyridine dicarboxylic acid halide in the presence of an acid-binding agent.

3 4 like the dyestutis themselves the photographic layers, methylolurea. This mixture is poured over a plate of glass which according to this invention contain at least one dyemeasuring 13 X 18 m. d dri d, Stuff of the Formula canhe P p known methods The plate is then exposed behind a step wedge, and and used for the production of color images. More esthe Silver image is developed in 1 pecially, the dyestuffs of the Formula 1 may be incorporated in a multi-layer material comprising on a support layer a layer dyed with a cyan dye and selectively sensidroxybenzene-sulfonatehydroquinone developer and fixed. The image dye is then bleached imagewise according tized to red, covered by a layer dyed magenta and Sela} to the amount of silver present, in a bath containing in tively sensitized to green and finally a layer dyed with a 1,000 Parts y Volume to 100 Parts y Volume of 32% dyestuff of the Formula 1 and sensitized to blue. 10 hydrochloric acid, to 120 parts of potassium bromide,

In general, the dyestuffs of the Formula 1 are y 30 to parts of thiourea and 0.001 to0.01 part of 2- fast to diifuston in the conventional layers. After drying a.mino 3 hydroxyphenazine they 5 not tend to opalesceint to The plate is subjected to an intermediate rinse and turbid in the gelatin layers and are easily reduced in the the excess silver 1s washed out in a bath containing in d bl a hing bath to harmless and/or easil Washed out z g groducts. y 15 1,000 parts by volume parts of sodium chloride, 100

The parts and percentages in the following examples Parts of crystalline pp sulfate 311d 50 Parts y Volume are by weight. of 37% hydrochloric acid. Finally, the plate is fixed Example 1 in the usual manner. A yellow color wedge is obtained 1.68 ml. of 1% aqueous solution of the dyestuif of the 20 which is pp to the Original Silver Wedge and i5 formula completely bleached out in the areas of the greatest initial H038 0-CH3 11 0-4? SOaH N=N-ONH-OO N oo-HN- N=N I HM) CH:

l S OaH HOaS Absorption maximum in water at A2338 m/L are added at 40 C. to 3.3 ml. of 6% aqueous gelatin. silver density. Such a yellow image may also be part of There are then added 3.3 ml. of a gelatin silver bromide a multi-layer color material. emulsion heated at 40 C. and, if desired or required, 1 to 3 Similar results are obtained by using instead of the 2 ml. of an aqueous solution of a spreading agent, for exdyestuif of the Formula 4 any one of the dyestuffs of ample saponin, and of a curing agent, for example dithe following Formulae 5 to 13:

( H038 ()CHICHQOH HOCHICHz? sgoarr N=NC NH-OC N CONHQN=N Absorption maximum in water at .=3S6 ma (6) HOaS 51.0311 N=NQNHCO N CONH N=N- HaC-CONH HSO-CO-J qH SOaH H0 8 Absorption maximum in water at A=3S2 111,11.

(7) H028 G $0.11 -N=N \lH-C O C O-NH- N=N- Q* *N Q H3O H:

SOaH H038 Absorption maximum in water at 1:366 mu HOaS SO H Absorption maximum in water at A=370 mp.

H0 8 SOgH N= QNE-C 0 N o OHNON=N- HN-OOCH: CHs-CO-ILTH SOaH H0 8 Absorption maximum in water at A=390 mu E038 SIOaH N=N NHC O C O-HN- N:

HN-COCHa CHaCO-NH SOaH HOz S Absorption maximum in water at A=392 my.

H0 8 SIOBH N=N NHOC N o0-HNC -N=N- )-CH:-OCH3 H;C-O-HnC- O SOaH 1103's Absorption maximum in water at )\:390 um Boss 803E N=NONH-00 N COHN-C N=N- SOaH HO S Absorption maximum in water at \=3( i2 mp.

1103's O-CHzCHa H CHaC-O 810 B -N=N NH-O O C ONN- N:

J)-CH CHa HaCHiC-O Absorption maximum in water at \=42l mg.

The dyestuif of the Formula 4 may be prepared in the following manner:

A solution of 60.6 parts of sodium 2-aminonaphthalene 4.8-disulfonate in 1.000 part of water is cooled with ice to 0 C. and then diazotized in the usual manner with 65 parts of 37% hydrochloric acid and 14 parts of sodium nitrite. A solution of 30.5 parts of 2-methoXy-5- methyl-l-aminobenzene in 300 parts of water and 30 parts of 37% hydrochloric acid, prepared at to 70 C., is cooled with ice to 5 C. and coupled with the solution of the diazo compound. After stirring for 24 hours at 8 to 15 C. the coupling to form the aminomonoazo dyestutf is complete. The acid suspension is heated to C. and then filtered at 30 C.

9 parts of the aminomonoazo dyestuif obtained in this manner are dissolved in 75 parts of water at pH=9. 2 parts of pyridine-2,6-dicarboxylic acid dichloride are dissolved by heating in 20 parts by volume of acetone 0 and this solution is added in portions at pH=8.5 to 9.5 to

Example 2 The following layers are produced successively on a 7 8 white opaque acetate film provided with an adhesive mide, 40 to 80 g. of thiourea, 35 to 80 g. of 30% sulfuric Coatmg: acid and, if desired, 0.01 g. of 2-amino-3-hydroxyphen- (l) Red-sensitive silver bromide emulsion in gelatin,

containing the cyan dyestuif of the formula azme;

Q- l OH a 3 HOsS- -SO3H l HOaS SO3H trio-o (2) Colorless gelatin layer without silver halide; (6) Rinsing for minutes;

(3) Green-sinsitive silver bromide emulsion in gelatin, (7) Bleaching out the residual silver for 5 minutes with containing the magenta dyestufi' of the formula a solution of 60 g. of crystalline copper sulfate, 80 g. of

| OH H0 8 80 11 HO l H0 8 H0 8 (4) Yellow layer, containing the dyestuif of the potassium bromide and 15 ml. of hydrochloric acid formula per liter of water;

Cl (8) Rinsing for 5 minutes;

(9) Fixing for 5 minutes as described above under 3,

0 I 30 and 61gb T (10) Rinsing for 5 minutes.

- SOEH The resulting positive image for viewing in reflected Q5 light is fast to light and of the permanence required for g documents. u 39 What is claimed is:

(5) Blue-sensitive silver bromide emulslon ll'l gelatin, 1, Photographic t ri l f th sil dye bleaching containing the yellow dyestuff of one of the Formulae 4 process, which comprises on a support a layer containing to 13. a silver halide emulsion and at least one dyestuff of the The gelatin layers may contain conventional additives, formula H0315 x X SIO H :nCD-mn-o 0G0 OHNCt -N=N Y N Y SO H HO S e.g. wetting agents, hardeners and stabilizers for the silver where X represents a member selected from the group halide. Each layer in general contains, per square meter consisting of a hydrogen atom, a halogen atom, an alkyl of film, 0.5 g. of the dyestufi concerned and silver brogroup, an alkoxy group, an alkoxyalkoxy group and an mide in an amount corresponding to 1 to 1.2 g. of silver. acylamino group and Y represents a member selected The film thus prepared is exposed under a color transfrom the group consisting of a hydrogen atom, and alkyl parency to red, green and blue printing light, and the group and a alkoxy group.

print is then developed through the following Stages: 2. Photographic material as claimed in claim 1 for the (1) Developing for 6 minutes in a bath containing per silver dye bleaching process, which comprises On a supliter of water 50 g. of anhydrous sodium sulfite, 0.2 g. port a layer containing a silver halide emulsion and at of l-phenyl-3-pyrazolidone, 6 g. of hydroquinone, 35 g. least one dyestulf of the formula H038 X X N=N- j: -Nn-oo N COHN- N=N Y Y 30:13: HOJS of anhydrous sodium carbonate, 4 g. of potassium browhere X represents a member selected from the group mide d 8- Of b6Il17;t1i3Z1e; consisting of a hydrogen atom, a halogen :atom, an alkyl Rmsmg for 5 minutes; group, an alkoxy group, an alkoxyalkoxy group and an (3) Fixing for 6 minutes in a solution of 200 g. of crysacylamino group and Y represents a member selected 5 f i z gg s ifii and 20 of Potassmm metabl from the group consisting of a hydrogen atom, an alkyl (4) Rinsing f 5 minutes; group and an alkoxy group. (5) Dye-bleaching for 3 to 12 minutes in a solution 3. Photographic material as claimed in claim 1 for the containing per liter of water 50 to 80 g. of potassium brosilver dye bleaching process, which comprises on a sup- 9 10 port a layer containing a silver halide emulsion and at 4. Photographic material as claimed in claim 1, wherein least one dyestuff of the formula the layer contains a silver halide emulsion and the dye- HOaIS iii If SIOaH -N=NONH-oo N COHNQN=N i Y SOaH HO S where X represents a member selected from the group stuff of the formula H033 O-GH: H3CO SIO H N=N -NHOC N -o 0HN-N=N- H32] (I111;

consisting of a hydrogen atom, a halogen atom, an alkyl 5. Photographic material as claimed in claim 1, wherein group, an alkoxy group, an alkoxyalkoxy group and an the layer contains a silver halide emulsion and the dyeacylamino group and Y represents a member selected stuff of the formula H03|s SOaH N=N *NHOC OOHNC N=N- N HaC-O OI IH HaC-C 0-1 11! SOaH H0 5 6. Photographic material as claimed in claim 1, wherein from the group consisting of a hydrogen atom, an alkyl the layer contains a silver halide emulsion and the dyegroup and an alkoxy group. stuff of the formula H035 O-GHaCHzOH HOCHzCHaO S0311 N= NHO 0 N C 0-HN N= H3O (5H3 SiO H 1103s References Cited UNITED STATES PATENTS 2,899,305 8/1959 Bossard et al. 96-99 3,264,109 8/1966 Anderau 9699 J. TRAVIS BROWN, Primary Examiner US. Cl. X.R. 

